Garuda has gain a massive boost in popularity. I wouldn't be surprised if we she is a common summon in future FF games. I really never hear of Fenrir.

I'm as casual as it gets when it comes to FF

The summons I've heard before playing FF14 (ff9 was my 1st game):
Ramuh
Ifrit
Bahumut
Titan
Alexander
Shiva
Leviathan